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No full textPoznańWe numerically investigated the characteristics of diode-end-pumped passively Q-switched solid-state Cr3+:LiSAF lasers. A Cr4+:YSO crystal is used as an intra-cavity saturable absorber. Our obtained results indicate the influences of resonator and pumping parameters on the characteristics of passively Q-switched solid-state Cr3+:LiSAF laser. Particularly, our numerical investigations are done in respect to the Cr3+:LiSAF laser medium of a very wide gain spectrum from 700 nm to 920 nm. Using a CW diode pumping at 670 nm and a Cr3+:LiSAF crystal of 3 mm long and 1 at.%, a stable generation of Q-switching nanosecond Cr3+:LiSAF laser pulse at 850 nm is obtainable with a pulse energy of about 2 mili-joule
No full textPoznańThe FEDERICA project is to create a virtual network environment that is dedicated to investigate and trial novel network protocols and services, as well as Future Internet architectural concepts and emerging applications. With this purpose in mind, a technology agnostic network infrastructure that consists of transmission devices, gigabit connections, and computing resources has been created. The physical FEDERICA network footprint is mapped to the existing GÉANT network links and additional NREN connections and creates its own infrastructure on top that allows resource virtualisation. The project partners do research on novel resource virtualisation techniques as well as share their operational experiences on virtualisation capable infrastructures during the project lifetime. Within the framework of FEDERICA, close cooperation has been established with various standardization bodies such as IETF, ITU-T, OIF, and IPsphere. Although, the main objective of the project is to create a physical environment that allows obtaining dedicated virtual slices of the infrastructure configured by the users, the project also facilitates information exchange, initiates technical discussions among the experts and disseminates scientific results primarily to national research and education network community. The FEDERICA project is partly funded by the European Commission under the INFRA-2007-1.2.2 “Deployment of e-Infrastructures for Scientific Communities” call of the Seventh Framework Program. The FEDERICA project [1] has been devised to provide support and research on current and Future Internet technologies and architectures. The project is linked to the European FIRE initiative [2] and the European Future Internet Assembly [3]. Other similar initiatives exist worldwide, e.g. GENI [4] in the United States in Europe, and AKARI [5] in Japan
No full textPoznańIn the framework of adiabatic approximation we perform numerical calculations of intensity distribution for the 41Π←11Σ+band system of NaLi based on the Franck-Condon (FC) principle. Comparison between the calculated FC factors and the corresponding spectral lines observed recently reveals a good agreement. In addition, the internuclear distances at which the most favorable transitions occurred are caculated
No full textPoznańThe growing demand for computational power causes that Grids are becoming mission-critical components in research and industry, offering sophisticated solutions in leveraging large-scale computing and storage resources. The nature a Grid in which resources are usually shared among multiple organizations offering resources under their control based on the “best effort” approach with no guarantee concerning the quality-of-service may be inadequate to support large-scale simulations. Requirements of such simulations often exceed capabilities of a single computing center causing the need to simultaneously allocate and synchronize resources belonging to many administrative domains whose functionality is missing in leading grid middlewares preventing researchers from executing large-scale simulations in grids. The paper presents tools and services that were designed to build multilayered infrastructure capable of dealing with computationally intensive large-scale simulations in the grid environment. The developed and deployed middleware enables computing clusters in different administrative domains to be virtually welded into a single powerful compute resource that can be treated as a quasi-opportunistic supercomputer. We describe the middleware developed in the QosCosGrid project and being enhanced under the PL-Grid national grid initiative, which provides advance reservation and resource co-allocation functionality as well as support for parallel large-scale applications based on OpenMPI (for C/C++ and Fortran) or ProActive for Java
